Wire tinning systems



July 28, 1959 Q HAUGWlTZ 2,896,869

' WIRE TINNING SYSTEMS Filed Dec. 13, 1957 INVENTOR. OTTO HAUGWITZ Zia/64a A TTORNEX United States Patent-"U I v WIRE'TINNING SYSTEMS Otto Haugwitz, Celle Saint Cloud, France, assigno to Ste. Aiionyiiie attorney-Dense, Paris, France, a French r hy I v Application December 13, 1957, Serial No. 102,702,

1 Claim. Grazia- 25 This'invention relates to methodsa'u'd apparatus of the'type used inthe tinning of copper wire and the like. In the conventional planefor. hottinning copper'wir'e, there is generally provided in sequence a feeder station, a pickling tank, a tinning tank, a wiping station, a cooling tank and a take-up station. The wire is generally passed through the tanks in sequence so as to be immersed in the tanks and is guided between the successive stations by being trained over suitable guide pulleys at least some of which are immersed in the tanks and hence exert a considerable retarding force on the wire. Because of this the linear rate of feed of the wire has necessarily been limited in such systems to comparatively low values on the order of 3 meters per second, since otherwise excessive tensile forces would tend to arise in the wire.

Wire tinning apparatus has already been proposed wherein the wire is made to run in a straight line through a bath of molten tin, the wire being introduced into the bath through the free surface thereof at a comparatively small angle, or alternatively, through a die nozzle positioned in the tank wall at the inlet side, and issuing from the tank by way of another nozzle supported in a rear wall of the tank, with the diameter of the outlet nozzle corresponding accurately to the desired diameter of the tin-coated wire having the desired depth of tin coating on it.

While systems of the type last described represent a substantial advance since they make it possible to impart of the wire linear velocities of the order of about meters per second, their velocity and hence the output capacity still remains limited. This is because the wire as it passes through its successive treating stations is still subjected to considerable frictional forces which increase rapidly with the rate of feed. Moreover, when it is attempted to provide wire tinning apparatus in which the rate of feed is substantially higher than the rates mentioned above, e.g. in the range of about 30 meters per second, it becomes necessary to use at the output or feed station a stationary or revolving feeder reel surrounded by a feeder casing to prevent the wire from ballooning out about the reel. The wire is subjected to friction from the inner surface of such a casing and the friction generated from this source, which also increases rapidly with the output or feed rate, combines its action with the other frictional forces enumerated above. Furthermore, in cases where the said output reel rotates, the retarding efiect on the wire is greatly increased during the initial stage when unreeling operations are started, due to the inertia of the reel.

Furthermore, whatever the type of hot wire tinning process used, the tensile strength of those portions of the wire immersed in the molten tin bath is greatly diminished due to the high temperature and can easily drop to a range wherein the wire in such portions will be unable to withstand the tension developed by the aforementioned retarding effects, and will break. For the various reasons enumerated, conventional tinning systems of 2,896,869 Patented July 28, 1959 can safely be increased to values unattainable hereto fore,

eb r srs d ri sa as he l i i t. capacity of ema n n w e: w enever ar e' s- According to" one'a'spec't of the invention; there is provided a high-speed hot wire-tinning system comprising a net" that feeder station employing a stationary feeder reel and a sla k-p venting '(or finiteness casingsurrounding tlie ree'l'in spaced 'relation with" it, atiiiiiing tank, and a recei'v'f or take-tip "station, characterized the interpesed betweefi saiareeaer semiarid tinning tank,

the wire being arranged to form at least one loop around said sheave and the sheave being driven at a peripheral velocity at least equal to the predetermined linear feed velocity which it is desired to impart to the wire.

Further objects, features and advantages of the invention will appear as the description proceeds, with reference to the accompanying diagrammatic drawings wherein Figs. 1 and 2, respectively, illustrate two embodiments of the invention given by way of example but not of limi tation.

Referring first to Fig. 1, the wire 1 issues from a stationary feeder reel 2 contained within a conventional recessed casing 3 which surrounds the reel in spaced re lation with it in order to prevent a ballooning-out of the wire as it feeds out from the reel. The wire 1 issuing from the casing 3 is passed over a conical sheave 4 driven from a suitable motor 5 at an angular speed such that the linear velocity at the bottom of the .groove of the sheave will at all times exceed the linear velocity of the wire. The wire may be caused to form say three loops about the winch 4. It will thus be appreciated that any tension force exceeding by a definite amount of say about 10% the tension present in the wire beyond the winch, will be directly taken up by the auxiliary motor 5. If it is desired to reduce the percentage of the tension taken up by the motor, the number of loops of wire around the winch need simply be reduced, and vice versa.

From the winch the wire is passed through a pickling tank 6, a tinning tank 7, a cooling tank 8, a wiper device 9 and is finally taken up on a receiver reel 10 driven by suitable driving means such as the motor 5a upon the shaft 5b of which the reel is mounted. Rotation of the take-up reel 10 imparts the desired feed velocity to the wire.

In the form of embodiment shown in Fig. 2, components corresponding to those in Fig. 1 have been referred to by the same reference numbers to which a prime has been added. In this embodiment the wire 1' issuing from the stationary outp ut reel 2 housed within its casing 3' is passed over a winch 4' and thence is trained about a guide pulley 11', prior to entering the pickling tank 6' followed by tinning tank 7, cooling tank 8 and wiper unit 9. Prior to the delivery of the wire to the revolving take-up reel, 10 driven by suitable driving means such as a motor 5a upon the shaft 5b of which the reel is mounted, the wire is passed about a further sheave 12 which is secured on a common shaft with the first mentioned sheave 4', the said shaft being freely rotatable.

The wire issuing at relatively low temperature from the cooling tank 8 rotates the sheave 12' and its rotation is transmitted by way of the common shaft to the input sheave 4' so that the input portion of the wire is fed at the same linear velocity as the output portion. Any retarding force that may be present ahead of the sheave 4 and such forces tend to increase with wire velocity as indicated earlier, is transmitted by way of the common shaft to the output sheave 12 and is thereby applied rd the cool wire entering the take-up reel 10'.

' The length of wire between the two sheaves 4' and 12 is, therefore, relieved of the major part of the tension stresses applied to the wire since it is subjeeted'only to relatively little friction from the components interposed between the two sheaves, and that friction is substantially independent of the velocity of the wire. Hence, the feed velocity can be increased to a value substantially equal to the velocity corresponding to the tensile limit of the wire when cold.

What I claim is:

In a wire hot-processing system, supply means providing a supply of wire, a hot treating station positioned to receive the wire downstream of said supply, a rotatable take-up reel means rotatable for pulling the wire from the supply means through said station, said takeup means being positioned substantially adjacent to said supply means, a pair of sheaves mounted on a common freely rotatable shaft, a first of said sheaves having a portion of the wire adjacent the supply means looped therearound and the second of said sheaves having a portion of the wire adjacent the take-up means looped therearound, and a pulley downstream of said first sheave but upstream of said second sheave to reverse the direction of travel of said wire in passing from said first sheave to said second sheave, whereby said first sheave is driven from the second sheave, as the second sheave is driven by the wire moving in response to said take-up reel.

References Cited in the file of this patent Martin May 3, 1949 

